1. Field
Apparatuses and methods consistent with exemplary embodiments relate to nano-piezoelectric generators and methods of manufacturing the nano-piezoelectric generators.
2. Description of the Related Art
Piezoelectric generators are devices for converting mechanical vibrations into electrical energy, and may be used as power sources for small-sized devices and sensors or may be used as sensors for sensing mechanical vibrations.
Recently, nanopiezotronics, which is a field which utilizes the piezoelectric phenomenon on a nanoscopic scale, has been researched. The piezoelectric efficiency of a nano-structure, in comparison to that of a bulk structure, may be improved because of a strain confinement effect. That is, in a bulk structure, strain generated due to stress occurs in a direction in which the stress is not applied, as well as in a direction in which the stress is applied, and thus the strain is dispersed. However, in a nano-structure, and in particular, in a nano-wire structure, that is, a one-dimensional nano-structure, strain is restricted to only a length direction of the nano-wire structure in which stress is applied, and thus a high piezoelectric coefficient may be obtained.
On the other hand, well known piezoelectric materials, such as lead zirconate titanate (PZT) and barium titanium oxide (BTO), are not suitable for nano-wiring and include substances that are harmful to human beings. Thus, recently, a material that is suitable for nano-wiring, such as ZnO or GaN, has been actively researched as a new nano-piezoelectric material.